Antirattling device for antenna masts



Dec. 14, 1948. R, L SCOTT ANTIRATTLING DEVICE FR ANTENNA MASTS Filed sept. 4, 1945 Patented Dec. 14, `1948 unire-n stares-e en'eenT or Fics ANTIRTTLENG'; DEVICE FOR ANTENNA MASTSL Russell. J. Scott, Kalamazoo, Mich.,.assignor. to

Shakespeare Products Company, Kalamazoo, Micha, av corporation of-l`l/Iichgan Application September 4, i945,l Serial. No..614,349

(Cl. Z50-33') 21Clain1s. l

rlhis inventionrelatesito improvements in radio antennas,.particularly, to telescopically.-collapsiblev antennas.. i

An important object of the invention is toprovide anti-rattlingy means: for .the telescopic. sectionsoi a .radiof antenna. mast,.whereby said seetions Will. be prevented. from having. vibratory. movement and resultant. rattling with relation to i the. particular sections -receiving the same.,

Moreover, itis an equally important. object oi the invention. to. provide aniantennamast `wherein rattling. or similar vibratory movement between the telescopically` engaged. sections constitutingl the same will be. prevented virresilvective-of the in dividual positioning of'said'sectionai. e., whether. they have been. moved .or .adjustedltoiully orpartially extended" positions..

In` the production. of telescopic typesof radio antenna masts, especially, .those typesused4 upon. motor driven vehicles. for. the reception. of radio intelligence,.as describ'edand claimed. inmy co pending application, Serial.No..596,127; ,l'ed May- 28,.1945, various forms of'anti-rattling devices are. provided to .theirtelescopically interengaged mast sections and it is thepurpose of the same to prevent rattlingor like vibratory movement thereof; also', to eliect movable retentionofl the. slidable. sections in pre-selected. longitudinally adjusted.v positions. Forthe better part, suchdevices have a" limited area, Contact or engagement With'theV telescopically receivedsection or sections, andusually, are positionedin a.receiving.section.ad-- jacent or'neartheA outer'end ofthe same. The resultof such positioning in the receiving section and"spot.'engagement.with the telescopi-- cally received section; is thatlnotwithstanding. fact-'that the'latter is frictionally gripped. and `releasably retained in a particular'longitudinally adjusted position with relationto. the former, theinner portion of. th'ejtelescopically received section, that is, the portion' of'itwithin the receiving. section, is permitted of lateral vibratory movement or rattling; within said receivingsectiom with the point of" frictional engagement .between the referredto anti-rattling.. device and' telescopi.-` cally received `section aiording4 or constituting.A a. fulcruming-like bearing. Not-only does, suclra-` construction permit. of "the above. mentionedfob jectionable rattling between the thus consti tuted"and"equipped radio antennamast sections,

but moreover; it" is manifest that. because of. the

described' lateralr movement or.. play.. of. an inner. portion' of a telescopically. receivedfsectionwithin its'receiving section,.suchv movement will, invari ably;` result in prematurewearingof vthe antenna,`

2'; mast assembly. and its-..partsto.the extent that, in a comparatively short time, the extendable sections of. theV mast. assemblyT will become incapable of. retaining. asecure adjusted, extended.

or. partially extended. relationship, and. addi-- tionally`inadequate or. faulty electricalconductivity.. I

Through tli-emediumof'my invention, there is provided. a. device `Whiclfi will positively prevent f rattling andlike vibratcry movement ,between .the

telescopically engaged sections of an equipped antenna masti`rresp ective of. the longitudinally adjusted:relationship` existing therebetween,.i. e., whether the telescopically engagedmast section or sections is. or are in telescopically. collapsed,

distendedor'partially distended position with respect to the: mast sectionreceiving the same; a device which will securely. retain the adjustable section orsections in a'djustedrelation, and moreover, ensure'const'ant and effectual electrical conductivity between the structural parts of the assembly.

The" foregoing, as welll as other. objects, advantages; andmeritorious teachings of theinvention; ,willF beinI part' obviousand in part. pointed out in* thel followingA detailed. disclosure thereof, whentaken'in" conjunction with. the accompanyingdrawing; t being' understood. that the particular fornrofinvention herein' isa precise and what is now considered* tol be, the. best mode of embodying its prin'ciples,'but that modications and changes may/ be" made' in specic. embodiments, withoutA departing fromA its essential features:

In lthe drawings;

Figurell is asid-e -elevatifm` of 'an' antenna. mast embody-ing; the invention. A

FigureVv 2 is an enlarge'dancl fragmentary side elevationoi the-antenna-mast, showing the antirattling deviceifarranged in certain of the mast.

sections in dotted lines, and also, showing the characterz oflengagem'ent" or' receptionv of the telescopicallysreceivedmastsections in their particularreceiving` sections;

Eigure 35 isi. an. enlargedl fragmentary detail in longitudinalfsection,` showing the manner in which telescopic: engagementv f is I. effected between certain of the mastlsections, andmoreover, the mode of: engagement: of.' one: end ofy one of the antirattlingi devices in. the upper end of its particular` section.;

Figure; 4 isf ae fragmentary; longitudinal sectionA showing the telescopic engagement betweenftlie tubular sections of the antennalmast', and also, showingfthefmannerrinlwhicliicertain offthe ends of the anti-rattling devices provided thereto are disposed and connected.

Figure 5 is an enlarged fragmentary longitudinal section through the lower or basal portion of the outermost tubular section of the improved antenna mast, illustrating the manner in which the lower end of its particular anti-rattling device is secured or connected to the same,

Figure 6 is a transverse section taken on the` line 6-6 of Figure 5, looking in the direction in which the arrows point. l

Figure 'i' is an end elevation of the lower end or basal portion of the antenna mast, illustrating the fixed connection of the lower end of the antirattling device provided to the outer mast section to its lower end, and

Figure 8 is an enlarged transverse section in detail, showing the cross-sectional curvature of one of the anti-rattling devices and the manner in which it is engaged with its particular or adjacent telescopioally engaged antenna' mast section.

Referring in detail to the drawings it will be noted that I have illustrated my invention applied to that type of antenna mast more often u-sed on automobiles for the reception of rado intelligence transmission of audio frequencies, though, of course, Yits usage is not necessarily so limited. Such a mast, generally, comprises a tubular main member l, a tubular secondary member 2 telescopically received in the latter, and a rod 3, ended'as at 4, telescopically received in the member 2. Thus, a telescopic antenna mast assembly is provided.

The members 2 and 3 are extendable with relation to the tubular main member l and to each other, whereby a mast of the particularly desired length (limitedrto the over-all extendablev lengths of the members l, 2 and 3) may be pro-` duced.

In order that the mast assembly may be attached and supported, a usually though not ne cessarily vertically positioned mounting bracket 5 is provided and snugly receives therein the basal portion of the tubular main member l. Suitable conductors (not shown) are provided to the mounting bracket 5 and, as will be understood, effect proper electrical conductivity between the members of the mast assembly and the radio apparatus equipped therewith.

The normally outer end portions of the tubular main and the tubular secondary members lI and 2, are annularly reduced or constricted, as indicated at l and 2. Thus, the main body portion of the member 2 is comparatively snugly and slidably received in and through the reduced end portion I of the member I, and the similar portion ofthe rod 3 is likewise slidably received in and 2through the reduced end portion of the member Outward longitudinal sliding disengagement of the tubular secondary member 2 from the tubular main member l' is prevented by annularly enlarging thenormally inner end portion of the member 2, as at 2B and snugly and slidably engaging the same within the body portion of the member l, inwardly ci its reduced portion, and by enlarging or flattening the normally inner end portion oi the rod 3, as at Saand slidably engaging the same within the body portion of the member 2, inwardly of its reduced portion 2', as illustrated by the Figures 2, 3, and 4 of the accompanying drawings.

To eiTect yieldable frictional--connection between the main member I and the secondary member 2, a strip-like body 6 of suitable electrically conductive spring metal of transversely arcuate or curved formation, is longitudinally engaged within the member I. This spring element is helically twisted or Wound at a relatively long pitch with its transversely dished surface inwardly disposed and has the normally outer end of the same arranged adjacent the annular shoulder formed in the coresponding end of the member i by the aforesaid annular end reduction l' thereof. The length of the helical spring body 6 is such that its remaining end is arranged near the adjacent and normally inner end of the member l where the same is blindingly engaged with and anchored by the longitudinally flattened side of an anchoring closure plug Xedly received in said member end. A longitudinal screw threaded bore 8 is preferably formed in the plug i yand is adapted to receive a connecting screw (not shown) appropriately engaging the mounting bracket 5 whereby the member l, and hence, the antenna mast assembly, will be connected to the latter.

Because of the helical formation of the spring body 6 andv its transverse area, plus its inherent spring properties, the same will maintain frictionalV contact with the adjacent walls of the member 2 (circumferentially thereof) substantially throughout its length, though slight lon gitudinal bodily adjusting movement thereof will be permitted by reason of the engagement of the innervend of the spring body with the annular internal shoulder of the reduced portion l' of the tubular member i.l

A second strip-like spring body 9, similar in construction and formation to the strip-like spring body 6, is longitudinally engaged within the member 2. Said strip-like spring body 9 is twisted or wound at a relatively long pitch with its transversely dished surface inwardly disposed. The normally outer end of the spring body 9 is arranged adjacent the annular shoulder formed in the corresponding end of the member 2 by its annular end reduction, as at 2. The length of this strip-like helical spring body 9 is suchthat itsrernaining end is arranged near or adjacent the corresponding and normally inner end of the member 2, i. e., its enlarged inner end portion'Z.l And to xedlyconnect this remaining end of the spring body 9 to the inner enlarged end portion 2an of the member 2, a plug Ill having a longitudinally disposed attened side is snugly inserted into said enlarged end portion 2a, as by driving fit, and is then locked or secured against further longitudinal movement withrelation to the member 2 by peening, as at il, or by other suitable means. It will be noted that the .outer end of the plug i0 is preferably iush with the correspondingend of the enlarged portion 2a of the member'Z.

The arrangement and formation of the striplike helical spring bodies 6 and 9 in the members l and 2,l is such that they will individually function to frictionally contact or'engage Yadjacent portions of the tubular secondary member 2 and the rod 3, respectively. That is to say, the intermediate portion of the strip-like spring body, because of its previously described mounting or arrangement within the tubular main member l, will frictionally Contact with and about that portion of the tubular secondary member 2 telescopically engaged in the latter member. Likewise. the intermediate portion of the strip-like helical spring body 9, will be frictionally engaged with and about the peripheral surface cf that portion of the rod 3 telescopically engaged within the tubular secondary member 2. In consequence, it will be readily understood that those portions of the member 2 and the rod 3 engaged within their respective receiving tubular members will be prevented from having relative vibratory movement, i. e., rattling, throughout their respective lengths. Moreover, it will be understood that both the tubular secondary member 2 and the rod 3 will be prevented from having fulcruming movement adjacent their respective points of entry into their particular tubular receiving members, to wit, the annularly reduced portions I and 2' of the tubular members I and 2. Such fulcruming movement, obviously, will be prevented because of the spring frictional engagement of the strip-like helical bodies 6 and 9 with the entire lengths of those portions of the secondary tubular member 2 engaged in the tubular main member I and the rod 3 telescopically engaged within the tubular secondary member 2.

At this point, attention is invited to the fact that a positively, accentuated frictional and a constantly yieldable contact or engagement between the strip-like helical spring bodies E and 9 and their respectively engaged portions of the member 2 and the rod 3, is effected by the transverse curvature of each of said bodies, hereinbefore described. The curvature of said bodies is of a greater degree than that of the outer peripheral surface of the tubular member 2 and the rod 3, .as is well indicated in Figure 8 of the accompanying drawings. Therefore, it will be seen that with arrangement of these strip-like helical spring bodies 6 and 9 between the tubular members I and 2 and between the tubular member 2 and the rod 3, each of said bodies will be under a more or less constant tension, and so, will eiect positive and increased frictional contact. Not only do the strip-like helical spring bodies B and 9 prevent relative vibratory movement or rattling of the telescopically engaged parts, hereinabove described, but it will also be understood and appreciated by workers skilled in this art, that said spring bodies will serve to movably though rmly retain the telescopically engaged or received secondary tubular member 2 and the rod 3 in any one of a plurality of relatively longitudinally adjusted positions, hence, insuring their satisfactory retention in fully or partially distended positions.

If desired, a suitable type of lubricant may be supplied within the tubular members I and 2 so that as the member 2 and the rod 3 are longitudinally moved therein, their outer peripheral surfaces will be coated with a Weather resistant lm, preventing corrosion, rusting or like impairment of such surfaces, and by the same token, insuring smooth sliding during adjustment operation.

If desired, the number of tubular members may be either increased or decreased, as may their diameters and lengths. Moreover, the herein illustrated and described formation of the constricted or reduced end portions I and 2 of the tubular mem-bers I and 2, respectively, may be varied without departing from either the spirit or the scope of this invention; it being the essence of such invention to provide an anti-rattling device for telescopic sectional body assemblies wherein those portions of such sections within their particular or respective tubular receiving members will be prevented from having vibratory relative movement entirely throughout their lengths.

I claim:

l, In combination with the telescopically engaged sections of an antenna mast, a length of strip-like cross-sectionally arcuately shaped spring material in one of the sections engaged about and generally lengthwise along the adjacent portion of the other section, the degree of curvature of the cross-sectionally arcuately shaped spring material being greater than the degree of curvature of adjacent portions of the telescopically engaged sections whereby to effect yieldable and frictional contact between said strip-like material and said sections.

2. In combination with the telescopically engaged cross-sectionally circularly shaped sections of an antenna mast, a length of helically formed strip-like electrically conductive spring material of cross-sectional arcuate shape in and disposed generally longitudinally of one of said sections and spirally engaged about and along an adjacent portion of the other section, the degree of curvature of the arcuate cross-sectionally shaped strip-like spring material being greater than the degrees of the cross-sectional curvature of adjacent portions of said telesccpically engaged sections, whereby to effect yieldable and frictional contact Ibetween said strip-like spring material and said'sections.

RUSSELL J. SCOTT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,179,415 Mace Nov. '7, 1939 2,226,522 Myers Dec. 24, 1940 FOREIGN PATENTS Number Country Date 133,580 Germany Oct. 4, 1901 

